Plan Mode And Explore Subagent

Definition

Two read-first workflow tools: Plan mode, where Claude proposes a plan and waits for approval before making any writes, and the Explore subagent, a read-only agent for fast codebase navigation.

Key points

• Plan mode proposes a plan and requires approval before any writes — contrasted with direct execution. Entered/exited via EnterPlanMode/ExitPlanMode; also selectable as permissionMode: plan or the --permission-mode plan flag.
• Explore subagent is a read-only built-in for fast navigation — Write/Edit are denied to it. The Plan built-in subagent is likewise read-only and runs in plan mode.
• Both are instances of the Minimal footprint principle: prefer reversible/read-only work until a plan is approved.
• Explore and Plan are two of the built-in subagents (alongside general-purpose).

Why it matters for the exam

• D3 (20% of scored content) tests choosing Plan mode / the Explore subagent for safe, reversible, read-only work — the correct answer for "investigate/plan before changing code" scenarios.

Common gotchas

• Plan mode blocks writes until approval — a plan is proposed, not executed.
• The Explore subagent cannot Write or Edit; don't route code-modification work to it.

See also

• Filesystem Subagents (.claude Agents)
• Session Resume And Fork
• CI CD Headless Flags
• Minimal footprint principle

Sources

• docs-tools-agents
• netlight-study-guide
• docs-claude-code-features